Conformational Change Observed in the Active Site of Class C ?-Lactamase MOX-1 upon Binding to Aztreonam.
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ABSTRACT:
SUBMITTER: Oguri T
PROVIDER: S-EPMC4505233 | biostudies-literature | 2015 Aug
REPOSITORIES: biostudies-literature
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Conformational Change Observed in the Active Site of Class C β-Lactamase MOX-1 upon Binding to Aztreonam.
Oguri Takuma T Ishii Yoshikazu Y Shimizu-Ibuka Akiko A
Antimicrobial agents and chemotherapy 20150608 8
We solved the crystal structure of the class C β-lactamase MOX-1 complexed with the inhibitor aztreonam at 1.9Å resolution. The main-chain oxygen of Ser315 interacts with the amide nitrogen of aztreonam. Surprisingly, compared to that in the structure of free MOX-1, this main-chain carboxyl changes its position significantly upon binding to aztreonam. This result indicates that the interaction between MOX-1 and β-lactams can be accompanied by conformational changes in the B3 β-strand main chain. ...[more]
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